Hartman, a young filmmaker at the time, planned to stay in the restaurant business just long enough to raise money to finish his first feature.
But by the time Hartman completed the film — "No Picnic," a gritty homage to the Lower East Side that won an award at the Sundance Film Festival — he and his Two Boots partners Doris Kornish and John Touhey were already hooked on running the Cajun-Italian eatery.
"We were going to spend six months doing it," Hartman, 56, an East Village resident, recalled recently. "But unexpectedly, the restaurant thing snowballed. The pizza became hugely popular. We wound up opening a branch across the street to catch the spillover. It just wanted to keep growing."
Now, 25 years later, Hartman has opened Two Boots locations everywhere from Hell's Kitchen and Grand Central Station to Baltimore and Los Angeles.
The restaurant, named for the similar geographical shapes of Italy and Louisiana, quickly became known for its crisp, cornmeal pizza crust and fanciful toppings ranging from Andouille sausage to alligator meat.
But the eatery also developed a reputation as a community-focused business.
Hartman decorated the original Two Boots with murals and mosaics from local artists, and even as he opened new locations, he tried to match the vibe of each restaurant to the surrounding neighborhood.
"Our philosophy has been to open a place we'd want to go to, not to do marketing studies to guess what the trends would be," Hartman said. "I want [the restaurants] to feel like they grow out of the sidewalk of the neighborhood. I hate places that feel like a spaceship has landed in the neighborhood."
While Hartman's philosophy has not changed in the past 25 years, the East Village has grown to be nearly unrecognizable.
Two Boots was one of the only restaurants in the area when it opened on Avenue A, and customers scoffed at the "Children Welcome" sign, pointing out that there were very few children to be found nearby, he explained.
"The neighborhood was pretty desolate back then," Hartman said. "If people were out late at night, they were either coming to Two Boots or they were going to score drugs on Second Street."
Junkies often passed out in Two Boots' bathroom, so Hartman got accustomed to removing the door from its hinges to keep them out.
As the East Village changed, Hartman began looking for different communities to invest in, often picking those that could be seen as depressing or vibrant, depending on the point of view: Bridgeport, Conn., Baltimore, Md., and Echo Park in Los Angeles.
In each spot, Hartman developed relationships with local nonprofits and artists, hosting poetry readings, open-mic nights and fundraisers.
"Giving back to the community has become as important a mission to us as serving great pizza," Hartman said. "When you open a business in a neighborhood, you're creating a contract with the customers. They're spending their money, and you're feeding them. But it's also important that you nourish each other in another way."
To celebrate Two Boots' 25th anniversary, the restaurant is sponsoring dozens of special events in the East Village this year, including a Mardi Gras Ball Tuesday night at the popular Bleecker Street venue (Le) Poisson Rouge. The 7 p.m. bash will raise money for the Lower Eastside Girls Club.
Other events will focus on the East Village's history, including a series of block parties co-sponsored by the Greenwich Village Society for Historic Preservation.
Looking back, Hartman said he has mixed feelings about the recent changes in the neighborhood where he raised his three children, including a son who now does technology work for Two Boots.
"Certainly it's a safer place for children," Hartman said. "But a lot of the edge and a lot of the uniqueness of the neighborhood has been steamrolled over and homogenized. We do everything we can to preserve it."